This peptide is histone H3 58-89 with monomethylation at Lys79. Lys79 methylation is mediated by DOT1 protein. Hypermethylation at Lys79 is associated with active gene transcription while hypomethylation is associated with transcriptional silencing. Hypomethylation at Lys79 is associated with Sir1 silencing proteins, which further block methylation by DOT1.